1. Atrial Fibrillation What is New in the 2006 ACC/AHA/ESC Guidelines HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation. May 2007

2. AF: Points of Focus Classification, epidemiology, and mechanisms Consequences of AF and aims of therapy Anticoagulation Rate control Rhythm control Rate vs. rhythm control: What to do? Catheter ablation for AF: What is the current status 2

3. AF: Classification First detected episode Recurrent AF (after 2 or more episodes) – Paroxysmal (spontaneous termination) – Persistent (lasting beyond 7 days, or termination with drugs or DCCV) Permanent AF: Sinus rhythm can not be restored Lone AF: Pts. younger than 60. No clinical or echo evidence for cardiac disease Nonvalvular AF: Cases without RMV disease, prosthetic heart valve, or valve repair. 3

4. AF Definition Paroxysmal AF: Recurrent AF (2 episodes) that terminates spontaneously within 7 days. Persistent AF: AF which is sustained beyond seven days, or lasting less than seven days but necessitating pharmacologic or electrical cardioversion. Longstanding persistent AF: is defined as continuous AF of greater than one-year duration. Permanent AF: Sinus rhythm could not be restored and a decision has been made not to pursue restoration of sinus rhythm by any means, including catheter or surgical ablation. 4

5. AF: Prevalence and Incidence Prevalence: – 0.4% - 1% in the general population – 8% in population over 80 years old – Lone AF: Less than 12% of all AF cases Incidence: – 0.1% per year in people < 40 years old – 2.0% per year in men > 80 years old – 10% is the 3-y incidence in HF patients 5

6. 0 10 20 30 Wolf et al. Stroke 1991;22:983-988. 50–59 60–69 70–79 80–89 AF: Prevalence and Strokes The Framingham Study % AF prevalence Strokes attributable to AF Age Range (years) 6

7. AF: Common Clinical Causes Cardiac causes Hypertension Coronary artery disease Congestive heart failure Pericarditis/Myocarditis Valvular heart disease Non-cardiac causes Electrolyte disturbances Thyroid dysfunction Ethanol intoxication Vagal/sympathetic imbalance Pulmonary disease Sepsis, febrile illness Appropriate work-up should be done and reversible causes identified and treated 7

8. AF: Mechanisms Rapidly firing atrial foci (hyperexcitability) Macroreentry with fibrillatory conduction (mother wave) Multicircuit reentry Remodeling acts to make multicircuit reentry a common final pathway Nattel et al. Ann Rev Physiol 2000;62:51-77. Multicircuit reentry (Mines, Garrey) Mother wave (Lewis) Hyperexcitability (Engelmann, Winterberg) 8